Apparatus for carrying a drilling mechanism along a desired path



Dec.'3, 1957 J. s. BELTZ r APPARATUS FOR CARRYING A DRILLING MECHANISMALONG A DESIRED PATH 6 Sheets-Sheet 1 Filed May 10, 1950 Dec. 3, 1957 J.s. BELTZ APPARATUS FOR CARRYING A DRILLING MECHANISM ALONG A DESIREDPATH 6 Sheets-Sheet 2 Filed May 10. 1950 [NVENTQ/Q, Jon N 5. Escrz,

Dec. 3, 1957 J 5 BELTZ 2,815,191

APPARATUS FOR CAR RYiNG A DRILLING MECHANISM ALONG A DESIRED PATHGSheets-Sheet 3 Filed May 10. 1950 Dec. 3, 1957 J, 5, BELTZ 2,815,191

APPARATUS FOR CARRYING A DRILLING MECHANISM ALONG A DESIRED PATH F1195.May 10, 1950 6 Sheets-Sheet 4:

IGO

Fig-10 JNVENTOQ; J OHN 5. BEIIFZ Dec. 3, 1957 J. 5. BELTZ APPARATUS FORCARRYING A DRILLING MECHANISM ALONG A DESIRED PATH Filed May 10, 1950 6Sheets-Sheet 5 ZN vE/YTo/Q; JOHN 5.Bn:1:rz,

O 4 o I w l O 1 Y l8 a I m 5 q m 0 a] o n 5 H H Q. m mm H Po I Dec. 3,1957 J. s. BELTZ 2,815,191

APPARATUS FOR CARRYING A DRILLING MECHANISM ALONG A DESIRED PATH FiledMay 10. 1950 6 Sheets-Sheet 6 fNVENTO/Q, JOHN S. BEL'TZ,

Q AA MIA 4m,

United States Patent APPARATUS FOR CARRYING A DRILLING MECHANISM ALONG ADESIRED PATH John S. Beltz, Columbus, Ohio, assignor to The JeffreyManufacturing Company, a corporation of Ohio Application May 10, 1950,Serial No. 161,047

6 Claims. (Cl. 255-51) This invention relates to apparatus for carryinga drilling mechanism along a desired path which is preferably, but notnecessarily, a straight line path, while the mechanism is performing adrilling operation.

One object of the invention is to provide an improved apparatus of thetype above set forth.

Another object of the invention is to provide improved apparatus of thetype above set forth, in which a drilling mechanism is carried upon aswingable boom and said boom is caused to expand and contract or retractas it is swung to carry or move the drilling mechanism preferably, butnot necessarily, along a straight line path.

In carrying out the foregoing object, it is another object of theinvention to provide in the improved apparatus mechanism by which theboom may also be swung about axes lying substantially at right angleswith respect to each other.

Another object of the invention is to provide an improved miningapparatus which is preferably, but not necessarily, in the form of atruck that carries a drill or drilling mechanism, and is capable offeeding the drill bit along a fixed rectinlinear path by simultaneouslyswinging and rectilinearly feeding the drill or drilling mechanism.

Still another object of the invention is to provide improved apparatusas set forth in the foregoing object, wherein the drilling mechanismincludes both a drill or drilling device and a torque wrench, the latterbeing adapted to drive threaded bars, rods or screws into openingsformed by the drill or drilling device in a mine room roof or ceiling.

Other objects of the invention will appear hereinafter, the novelfeatures and combinations being set forth in the appended claims.

In the accompanying drawings:

Fig. 1 is a side view in elevation of a mining apparatus including atruck that embodies the features of the invention;

Fig. 2 is a view in plan of the apparatus seen in Fig. 1;

Fig. 3 is a View on a larger scale of a portion of the boom apparatusand associated mechanism of the apparatus seen in Fig. 1;

Fig. 4 is a view in plan of the mechanism seen in Fig. 3;

Fig. 5 is a side view in elevation, with a portion broken away, of aframe and an associated stub shaft that form parts of the boom mechanismof the apparatus;

Figs. 6 and 7 are a side elevational and a plan view, respectively, ofanother portion of the boom mechanism of the apparatus;

Figs. 8, 9 and are sectional views, the views being taken substantiallyon lines 88, 9-9 and 1010, respectively, of Fig. 3;

Fig. 11 is a view in plan of a drilling device and torque wrench unitcarried by the machine as shown in Figs. 1 and 2;

Fig. 12 is a view in section, the section being taken on line 1212 ofFig. 11;

Fig. 13 is a view in plan of a modified form of drilling device andtorque wrench unit; and

Fig. 14 is a view in section, the section being taken substantially online 14-14 of Fig. 13.

In mining operations it is customary generally to provide in the minerooms, passageways, etc., timbering or other structure for supportingthe mine roof or ceiling to prevent it or a portion of it from falling.The installation of this timbering or other roof supporting structurewhich is costly and time consuming, is now being superseded by drillinglong bores of relatively small diameter upwardly into the mine roof orceiling and then by inserting in these bores long threaded bars, rods orscrews that function to tie the lower strata of rock, shale, coal orother material immediately adjacent the top of the mine room or passageto the rock stratum thereabove, thereby preventing the lower strata frombreaking and falling into the mine.

The apparatus shown in the drawings was particularly devised fordrilling the aforementioned holes or bores in the mine roof or ceilingand then for screwing or driving the aforementioned along bars, rods orscrews into the previously drilled holes. This apparatus includes atruck 10 having a main frame or body 11. Truck 10 is provided adjacentits front end with a pair of traction wheels 12 carried upon the ends ofan axle 13. Adjacent its rear end the truck 10 is provided with a pairof steering wheels 14 carried upon the ends of an axle 15 that ispivotally mounted at 16 to main frame 11.

At one side of the truck 10 and rearwardly of the rear axle 15 and oneof the wheels 14 there is an operators platform or station 17 at whichis positioned a steering wheel 18 and other control mechanisms, by whichan operator may control the operation of the truck 10. It may bementioned that the operator may seat himself upon platform 17 so that hemay face in that direction in which he desires to drive the truck 10.Adjacent the operators platform 17 there is a cable reel mechanism 19that carries an electric cable, not shown, through which electriccurrent is supplied to the electrical apparatus of the truck.

Truck 10 also includes a main electric motor 20 at one side of the mainframe 11 and between one of the wheels 12 and 14. Electric motor 20drives through reduction gearing contained in a housing 21 a pair ofhydraulic pumps 22. Pumps 22 are the main hydraulic pumps of theapparatus and are employed to drive the traction wheels, etc., of thetruck, as well as to operate other hydraulic motors hereinafterdescribed.

Adjacent its front end the main frame 11 of truck 10 carries andpreferably includes a turntable or platform 23 that supports the rearend member or frame 24 of an expansible and contractable or retractableboom as sembly 25. Boom assembly 25 is carried in cantilever in aconventional manner upon the platform 23 by the rear end frame member 24thereof which is pivoted at 26 to swing upon the platform 23 about anupright axis, whereby the boom may be swung laterally or from side toside by a reversible hydraulic motor and reduction gear unit 27 carriedby the member 24. The frame or member 24 of boom assembly 25 at itsfront end is substantially square in cross-section and at two of itsopposite sides it carries spaced side plates 28 and 29 (see particularlyFigs. 3, 4 and 5). Plates 28 and 29 are interlocked with and secured tothe front end of member 24 by square keys 30 and cap screws 31. Plates28 and 29 are generally L-shaped and their forward portions or legsextend downwardly. Adjacent their bottoms these forward downwardlyextending portions or legs are interconnected by a cross-plate or bar 32bolted at its ends to lugs 33, one of which is welded to each plate 28and 29.

Plates 28 and 29 each includes a substantially L-shaped opening or camslot 34 which slots 34 are aligned with each other and provide camsurfaces for a linkage mechanism described hereinafter. The cam surfacesprovided by each opening 34 is reinforced by a shoulder member 35 weldedto each of the plates 28, 29. Plate 28 includes a second opening or camslot 36 (see Fig. positioned forwardly of the first cam slot 34. Spacedlaterally outwardly of the plate 28 is a cam plate 37 that includes acam slot 38 that corresponds in shape and is in alignment with cam slot36 in plate 28. Cam plate 37 is carried by a curved plate 39 welded toboth it and the plate 28.

Spaced side plates 28 and 29 carry between them a forwardly extendingarm 40 that has welded to its rear end a pair of spaced upwardlyextending legs 41. Adjacent its top each of the legs 41 is provided witha spacer abutment 42 that abuts one of the spaced side plates 28 or 29to limit sidewise movement of the arm 40 between them upon a pivot pin43. Pivot pin 43 extends through aligned openings in the spaced sideplates 28, 29, the spacer abutments 42 and legs 41. will be seen thatthe arm 40 is free to swing pivotally about the horizontal axis of pivotpin 43 and between the spaced side plates 28 and 29.

Arm 40 is adapted to fit and telescope into the rear end of a boommember 44 and for this purpose its front portion is circular incross-section and carries two diametrically oppositely spacedlongitudinally extending keys 45 (see particularly Figs. 5 and 8). Atits front end arm member 40 carries a removable bracket 46 adapted toreceive the piston rod of a double acting hydraulic motor or jack 47(see Fig. 9). Bracket 46 is secured to the front end of arm 40 by a key48 and cap screws 49. (See Fig. 5.)

The member 44 of boom assembly includes a rear tubular portion 50, afront tubular portion 51 and a pair of side bars or straps 52 welded attheir ends to the portions 50 and 51 and gussets 53 thereon for spacingthe portions 50 and 51 apart. Rear portion 50 of member 44 is bored tofit over arm and it is provided with two keyways 54 that receive thekeys on arm 40. The keys 45 and keyways 54 prevent relative rotation ofarm 40 and rear portion while permitting the latter and consequently themember 44 to slide longitudinally or rectilinearly upon the arm 40.

Each of the bars or side straps 52 of boom member 44 has adjacent itsrear end an outwardly projecting stub shaft 55 welded thereto thatcarries a roller 56. Stub shafts 55 lie upon a common axis and projectinto the aligned cam slots 34 in side plates 28 and 29 so that rollersor cams 56 engage and are guided by the walls of the slots as the boom,including portions 40, 50, 52 and 51, is swung about the pivot pin 43.The cam rollers 56 and cam slots 34 cooperate in forming a linkagebetween the rear portion, main frame or mounting means of the boomassembly including the member or portion 24 and the spaced side plates28 and 29. As the member 44 of boom assembly 25 is swung about the pivotpin 43 the linkage, including the cam slots 34 and cam rollers 56, camor move the member 44 longitudinally or rectilinearly along the arm 40,whereby the front end of boom portion 51 follows along or describes avertical straight line path.

The member 44 of boom assembly 25 is swung about the horizontal axis ofpivot pin 43 by the hydraulic piston motor or jack 47. Jack 47 iscarried between the spaced side plates 28, 29 of the frame of the boomassembly 25 by a pair of trunnions 57 that project from the body of thejack into aligned openings 58 in the side plates 28 and 29. Hydraulicjack 47 has a telescoping piston that includes a piston rod 59 and apiston sleeve 60 that telescope with each other and with the body of thejack 47. Piston rod 59 extends upwardly between the two arms of bracket46 on arm 40 and is pivotally connected thereto by a pin 61.

From the description thus far given, it will be seen that when jack 47is expanded the member 44 of boom assembly 25 will be swung upwardlyabout the horizontal axis of pivot pin 43, and that when jack 47 iscontracted the member 44 of boom assembly 25 will be swung in a reverseor downward direction about said horizontal axis of pin 43. It will alsobe seen that when the member 44 of boom assembly 25 is swung eitherupwardly or downwardly it will be moved by the linkage including camslots 34 and cam rollers 56 longitudinally or rectilinearly along thearm 40, whereby the front end of the boom assembly 25 will follow ordescribe a straight line path.

At its front end the front tubular portion 51 of boom assembly 25includes a yoke 62 welded to the end of tubular portion 51 throughgussets. Yoke 62 carries for pivotal movement through aligned trunnionpins 63 (see Fig. 11) the frame 64 of a combined drill bit drivingmechanism and torque wrench 65. T runnion pins 63 provide a pivotalconnection between the yoke 62 and the combined drilling mechanism andtorque wrench 65 on a transverse horizontal axis. Frame 64 of drill ordrill bit driving mechanism and torque wrench 65 includes an outer framemember 66 and this outer frame member 66 is pivoted for swingingmovement to the yoke 62 by the pins 63 which extend through it and intothe forwardly extending spaced arms 67 of yoke 62. Pins 63 are locked inthe arms 67 by set screws 68.

As best seen in Figs. 3, 4 and 11, the rear member of outer frame 66carries a pair of spaced rearwardly extending lugs or ears 69 thatreceive through a pivot pin 71 the front end of a rod or link of asecond linkage mechanism. Rod or link 70 extends rearwardly from theouter frame 66 along one side of boom member 44, and its rear end ispivotally connected through a pivot connector 72 to the front end of arod 73. Rod 73 is carried for longitudinal movement through a bracket 74welded to the front end of one of the side bars or straps 52 of member44 (see Figs. 6, 7 and 9), and upon its rear end (see Fig. 10) there iswelded a block 75. Block 75 forms a tongue that extends between the sideplate 28 of boom assembly 25 and the cam plate 37 and it carries througha bushing 76 a pin 77, upon the ends of which there are cam rollers 78and 79. Cam roller 78 operates in the cam slot 36 in side plate 28 andcam roller 79 operates in the cam slot 38 in cam plate 37. Pin 77 isslotted or notched at its outer end to receive the end of a fasteningplate 80 bolted at one side of the block 75 and extending over the camplate 37.

It will be seen that when the front boom member 44 is swung by thehydraulic jack 47 the second linkage, including the cam slots 36, 38,cam rollers 78, 79, and rods or links 73 and 70, will shift or swing theouter frame 66 and the combined drill and torque wrench 65 on thetrunnion pins 63. The shape of cam slots 36, 38 is such that avertically extending drill bit carried by the combined drill and torquewrench 65 will remain in a vertical position when the boom member 44 isswung about the axis of pin 43. Rod or link 70 of the second linkagemechanism includes a connecting device 81 that permits the combineddrill and torque wrench 65 to pivot to a limited extent upon thetrunnion pins 63 against compression springs. Connecting device 81 iscomprised of a pair of spaced tubular end members 82 and 83 spaced apartby a pair of straps 84. End member 83 is welded upon the rear end of theforward member 85 of rod 70. and end member 82 slidably receives theforward end of the rear member 86 of rod 70. The forward end of rodmember 86 extends between the straps 84 and into the end member 83welded to rod member 85. Rod 86 carries a collar 87 locked theretobetween the straps 84. Springs 88 are interposed between abutment collar87 and the end members 82 and 83. It will be seen that the connectingdevice 81 causes the rod or link 70 to be resiliently expandable andcontractable.

' The frame of the combined drill and torque wrench 65 includes ahousing casting 89 carried by the outer frame 66 through three capscrews 90. Housing or body casting 89 together with suitable closureplates that cooperate with it forms a housing structure that includes anupper gear box 92 and a lower gear box 93. Top cover plate 94 includesan upstanding bearing receiving collar 95 in which there is ananti-friction bearing 96. Bearing 96 at its bottom abuts a shoulder onthe plate 94 and is retained within the collar 95 by a snap ring 97. Theinner race of bearing 96 receives the boss 98 of a hub 99, the bossbeing secured within the race by a snap ring 100. Hub 99 is flanged atits outer periphery to form a collar that extends downwardly over andcooperates with the upstanding bearing receiving collar 95 to form alubricant and dirt seal for the upper gear box 92.

Body casting 89 carries a rotary hydraulic motor 101, the shaft 102 ofwhich extends into the upper gear box 92 and is axially aligned with thehub 99. Shaft 102 is supported by an anti-friction bearing 103 and itsend projects into and drives a gear 104. Gear 104 includes a centralupwardly extending splined boss 105 that extends into and engages theboss 98 of hub 99 to drive the latter. Hub 99 is provided upon its topsurface with a threaded stud plate 106 fastened thereto by a pluralityof screws 107. The threaded stud of stud plate 106 is adapted to receivea drill bit receiving socket 91.

Gear 104 meshes with and drives a gear 108 carried on the upper end of ashaft 109 that extends through a tubular portion of the body casting 89and into the lower gear box 93. Shaft 109 is carried on spacedanti-friction bearings 110. The lower end of shaft 109 carries a gear111 that meshes with a reach gear 112 that meshes with a gear 113. Reachgear 112 is carried by an anti-friction bearing 114 mounted upon astationary shaft 115, one end of which is carried by the body casting89, and the other end of which is carried by the cover plate 116 for thelower gear box 93. Gear 113 drives an upstanding shaft 117 also carriedupon anti-friction bearings, one in the body casting 89 and the other ina cup formed on the cover plate 116. Shaft 117 drives a torque wrench118 that may be of any standard construction. The body 119 of torquewrench 118 is secured to the body casting 89 by a plurality of capscrews. Torque wrench 118 includes a driving shaft 120 that receives asocket 154 (see Fig. 12) adapted to receive the ends of the previouslymentioned rods, bolts or screws that are to be threaded into the holesdrilled in the mine roof.

In Figs. 13 and 14 there is shown a modified form of combined drill andtorque wrench 121. In this embodiment the combined drill and torquewrench is trunnioned directly to the yoke 62 by suitable pivot pins 124(see Fig. 14) that fit into sockets 123 formed in the body casting 126.Body casting 126 cooperates with a cover plate 127 on the bottom thereofto form a gear housing 128 and it carries a rotary hydraulic motor 129,the drive shaft 130 of which extends downwardly into the gear housing128 and is supported therein by an antifriction bearing 131 clampedbetween the main body casting 126 and the housing of motor 129 by thelatter. Drive shaft 130 carries within the gear housing 128 a gear 132that meshes with a gear 133 and a gear 134. Gear 133 is carried by theend of an upright shaft 135 mounted at its lower end in a tapered rollerbearing 136 carried by the casting 126. The upper end of shaft 135 iscarried by a roller bearing 137 received in a cap 138 fastened to thebody casting 126 by a plurality of cap screws 139. Cap 138 includes ashoulder portion 140 that extends into the body casting 126 and abuts alubricant retainer 141. Retainer 141 is in the form of a collar thatfits the shaft 135 closely to retain lubricant about roller bearing 137.

The top of shaft 135 fits into and drives an internally threaded hollowtapered member 142. Tapered member 142 includes a peripheral downwardlyextending flange portion 143 that fits over and cooperates with anupstanding collar 144 on cap 138 to provide a top dirt and lubricantseal for the bearing 137. The tapered member 142 is secured to shaft bya cap screw 145 threaded into the upper end of shaft 135. The centralbore of the tapered member 142 is internally threaded and it receives alocking or jam screw 146 that abuts the cap screw 145. Looking screw 146receives a socket 147 that is adapted to receive a drill bit.

The gear 134 drives a shaft 148 that is carried by two anti-frictionbearings, one in the body casting 126 and the other in a cup formed onthe cover plate 127. Shaft 148 drives a torque wrench 149. Torque wrench149, like torque wrench 118, may be of any suitable construction and inthe embodiment shown it includes a main body 150 that is driven by theshaft 148 and includes lugs 151 that cooperate with a lug 152 on thebottom of the driven shaft member 153 of the torque wrench Shaft 153receives a socket 154 adapted to receive the heads of the aforementionedrods, screws or bolts. The housing of torque wrench 149 is formed as anintegral part of main body casting 126 and is closed at the top by acollar or cap 155. Body casting 126 is provided with a lug 125 (Fig. 13)that receives the front end of rod or link 70. However, with thisembodiment of the torque wrench the front end of rod 70 will bebifurcated to fit over the lug 125.

Referring now particularly to Fig. 9 of the drawings, the side plate 29carries a double acting hydraulic piston motor or jack 156 that issecured to it by suitable bracket structure including clamps 157 weldedto a plate 158 which in turn is welded to the side plate 29. The pistonrod 159 of jack 156 is formed at its lower end as a ball 160 and itcarries a foot or base plate 161 provided with a plurality of downwardlyextending studs or pins 162. Jack 156 is used as a supplemental supportfor supporting the rear portion or frame of the boom assembly 25 whilethe drill is being fed upwardly to bore a hole in the mine roof orceiling by extending its piston rod 159 so that the foot or base plate161 rests upon the ground, as indicated in Fig. 3 of the drawings.

Front boom member 44 carries a plurality of hydraulic valves 163 thatmay be actuated by an operator standing adjacent them to control thesupply of hydraulic fluid from the pumps 22 to the rotary hydraulicmotor 101 or 129, the motor 47 and the jack 156 and other hydraulicmotors of the mining apparatus.

In the operation of the apparatus the truck is driven to adjacent thelocation where it is desired to drill a hole upwardly into the mine roofor ceiling. With the boom lowered, as seen in Fig. l, and the combinedtorque wrench and drill resting upon or adjacent the mine room floor, adrill bit, not shown, is placed in the socket 91. The motor 101 is thenstarted to drive the drill bit, and jack 47 is operated to elevate themember 44 of boom assembly 25. As the boom is elevated, of course, thedrill bit will enter and bore an opening upwardly into the mine roof orceiling. Because of the linkage, including the cam elements 34 and 56,the front end of front tubular portion 51, and the axis of the trunnionpins 63, and consequently the combined drill and torque wrench, willmove vertically upwardly; that is, they will move along a straight orrectilinear path, thereby to feed the drill bit directly into the mineroom ceiling without bending it. As the boom is elevated the secondlinkage, including the cam elements 36 and 38 and the rollers 78 and 79,will cause the frame of the combined drill and torque wrench to swingupon the mounting pins 63 to maintain the axis of the drill bitvertical.

Upon the completion of the drilling of one or more holes in the mineroof or ceiling by the drill bit, the forward portion 44 of boomassembly 25 will be lowered and the drill bit removed therefrom. Theoperator will then start into each of the drilled openings in the mineroof or ceiling a threaded rod or screw and he will then shift theforward portion of the boom 44 so as to cause the socket 154' on theshaft 121 of the torque wrench to engage the head of this rod or screw.With the head of the rod or screw in driving relation with the torquewrench 118, the hydraulic motor 101 is operated to cause the torquewrench to swing or drive the rod or screw upwardly into the mine roof orceling. It will, of course, be seen that when the rod or screw isthreaded into the mine room ceiling to such an extent that its head or awasher on the screw engages the mine room ceiling. the torque wrenchwill slip to prevent stripping of the threaded relation between thescrew or rod and the rock strata of the mine roof or ceiling.

When particularly hard drilling is encountered the jack 156 may beemployed to assist in supporting the rear frame portion of the boomassembly 25 to prevent downward swinging or tilting of it.

From the foregoing description it will be seen that there is provided adrilling apparatus particularly adapted to drill holes in a mine roomroof or ceiling and then to drive into the drilled holes threaded rodsor bars that serve to tie the strata that forms the roof of the minetogether to prevent cave-ins and the like. It will also be seen that theboom mechanism which carries the combination drill and torque wrench maybe swung laterally about the vertical axis of the pivot 26 as indicatedin Fig. 2 of the drawings, that its forward portion may be swung aboutthe horizontal axis of the pivot pin 43, and that when the forwardportion 44 is so swung the forward end of it moves to describe astraight line path.

While in the embodiment of the invention shown the truck and boom carrya combination drill and torque wrench, it is obvious that any miningmechanism may be substituted for the combination drill and torque wrench65 or 122.

Obviously those skilled in the art may make various changes in thedetails and arrangement of parts without departing from the spirit andscope of the invention as defined by the claims hereto appended, andapplicant therefore wishes not to be restricted to the preciseconstruction herein disclosed.

Having thus described and shown an embodiment of the invention, what isdesired to secure by Letters Patent of the United States is:

1. Drilling apparatus including in combination a frame, an extensibleand retractable boom, a drilling mechanism, pivotal mounting meansmounting said drilling mechanism on one end of said boom for pivotalmovement about an axis, mounting means mounting the other end of saidboom on said frame for swinging movement, means for swinging andextending and retracting said boom for causing said drilling mechanismto follow a straight line path when said boom is swung, and adjustingmechanism including a link and cooperating cam elements connecting saiddrilling mechanism and frame for adjusting said drilling mechanism aboutsaid axis as the boom is swung.

2. A mine roof drilling apparatus including in combination a truckhaving a main frame, a turntable on said truck main frame, a boomsupporting frame on said turntable, motor means for rotating said boomsupporting frame, an extensible boom, mounting means mounting the innerend of said boom on said boom frame for swinging movement about ahorizontal axis, motor means for swinging said boom as aforesaid, adrill mechanism including a drill frame, a yoke on the outer end of saidboom, pivotal mounting means mounting said drill frame in said yoke forpivotal movement on a horizontal axis, adjusting mechanism includingcooperating cam elements interconnecting said boom frame and the outerend of said boom for adjusting the latter longitudinally when said boomis swung about said first-named horizontal axis, adjusting mechanism forswinging said drill frame in said yoke with respect to said outer end ofsaid boom as the boom is swung about said first-named 8 horizontal axis,said adjusting mechanism including a linkage having cooperating camelements connecting said drill frame and said boom supporting frame, anda jack means adapted to aid in supporting said boom supporting frame.

3. A mine drill apparatus including in combination a truck having a mainframe, a turntable on said main frame, a boom supporting frame on saidturntable, a drill bit driving mechanism, pivotal mounting meansmounting said drill bit driving mechanism on the outer end of said boomfor pivotal movement, mounting means mounting the inner end of said boomon said frame for swinging movement, adjusting mechanism interconnectingsaid boom supporting frame and the outer end of said boom for adjustingsaid outer end of said boom rectilinearly as it is swung, said adjustingmechanism including cooperating cam and link elements interconnectingsaid boom and boom supporting frame, and adjusting mechanism forswinging said drill bit driving mechanism with respect to said boomincluding a link and cooperating cam elements connecting said drill bitdriving mechanism and said boom supporting frame for adjusting saiddrill bit driving mechanism with respect to said boom as the latter isswung.

4. A drilling machine including a frame, an extensible boom pivotallymounted at one end on a transverse horizontal axis and carried by saidframe, drill mechanism pivotally carried by the other end of said boomon a transverse horizontal axis and movable upwardly and downwardly assaid boom swings on said first named horizontal axis, means forextending and retracting said boom as it swings to direct the movementof said drill mechanism along a straight vertical line, and cam andlinkage mechanism interconnecting said drill mechanism and said frame toswing said drill mechanism on its horizontal axis as said boom swings.

5. A drilling machine including a frame, an extensible boom pivotallymounted at one end on a transverse horizontal axis and carried by saidframe, drill mechanism pivotally carried by the other end of said boomon a transverse horizontal axis and movable upwardly and downwardly assaid boom swings on said first named horizontal axis, means forextending and retracting said boom as it swings to direct the movementof said drill mechanism along a straight vertical line, and linkagemechanism interconnecting said drill mechanism and said frame includingmeans holding said drill along a fixed axis as said boom swings.

6. A mine drill apparatus including in combination a supporting frame,an extensible boom, a drill bit driving mechanism, pivot means mountingsaid drill bit driving mechanism on the outer end of said boom, mountingmechanism mounting the inner end of said boom on said frame for swingingmovement including a carrying element, a boom carrying arm, pivot meansconnecting said arm to said carrying element, mechanism includingcooperating cam and link means interconnecting said carrying element andsaid frame for adjusting said boom rectilinearly as it is swung, andadjusting mechanism for swinging said drill bit driving mechanism on theouter end of said boom as the boom is swung, said adjusting mechanismincluding a resilient linkage having cooperating cam elements connectingsaid drill bit driving mechanism and said boom for swinging the drillbit driving mechanism as aforesaid.

References Cited in the file of this patent UNITED STATES PATENTS1,885,295 Robinson Nov. 1, 1932 2,409,843 Feucht Oct. 22, 1946 2,410,508Lamme Nov. 5, 1946 2,532,079 Beltz Nov. 28, 1950 2,557,637 Danuser June19, 1951 2,581,535 Jackson Jan. 8, 1952

